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Altingiaceae comprise three genera: Altingia, Liquidambar, and Semiliquidambar. These three currently recognized genera represent a rapid radiation and have been difficult to separate reliably. Semiliquidambar has recently been shown to be hybrids of species of Altingia and Liquidambar. This result had been expected for some time. [5]Altingia and Liquidambar are known to be paraphyletic and a revision of the family is being prepared. [4] Many of the species are closely related, and distinctions between them are likely to be artificial. Consequently, there is disagreement over the number of species. Altingia currently has six to eight recognized species. Liquidambar has four or five species, and Semiliquidambar has two to four. [4]

The name "Altingiaceae" has a long and complex taxonomic history. Some attribute the name to John Lindley, who published it in 1846. Others say that the authority for the name is Paul F. Horaninov, who described the group in 1841. [6] In the nineteenth and twentieth centuries, tha family Altingiaceae was not generally accepted. Most authors placed these genera in Hamamelidaceae and this treatment has been followed in some recent works as well. [7] In the twenty-first century, however, molecular phylogenetic studies have shown that including Altingiaceae in Hamamelidaceae makes Hamamelidaceae paraphyletic. The Angiosperm Phylogeny Group recognizes four families in the lineage including Altingiaceae. Cercidiphyllaceae and Daphniphyllaceae are sister. This clade is sister to Hamamelidaceae and these three families are sister to Altingiaceae. The clade is sister to Paeoniaceae[8]

^Zhe-Kun Zhou, William L. Crepet, and Kevin C. Nixon. 2001. "The earliest fossil evidence of the Hamamelidaceae: Late Cretaceous (Turonian) inflorescences and fruits of Altingioideae". American Journal of Botany88(5):753-766.